UNITED NATIONS, April 17

Britain and China faced off on Tuesday in the first United Nations Security Council debate on climate change, with Britain pushing the issue and China saying the 15-member body had no competence to deal with it.

The British foreign secretary, Margaret Beckett, who presided over the meeting, argued that the potential for climate change to cause wars made it an issue for the Security Council, the most powerful United Nations body, but one that has a mandate to deal only with international peace and security.

“Our responsibility in this Council is to maintain international peace and security, including the prevention of conflict,” said Ms. Beckett, whose country holds the current Council presidency. “An unstable climate will exacerbate some of the core drivers of conflict, such as migratory pressures and competition for resources.”

She noted that President Yoweri Museveni of Uganda, whose economy depends on hydropower from a reservoir depleted by drought, had called climate change “an act of aggression by the rich against the poor.”

“He is one of the first leaders to see this problem in security terms,” she said. “He will not be the last.” She called the debate “a groundbreaking day in the history of the Security Council.”

But China’s deputy ambassador, Liu Zhenmin, was blunt in rejecting the session. His nation’s economy is growing fast and still depends heavily on coal and other fossil fuels that scientists say are contributing to climate change.

“The developing countries believe that the Security Council has neither the professional competence in handling climate change, nor is it the right decision-making place for extensive participation leading up to widely acceptable proposals,” he said.

Russia, China, Qatar, Indonesia and South Africa, among others, also said the Security Council was not the place to take concrete action, though no resolution is expected.

Pakistan argued against the debate on behalf of 130 developing nations, with many saying the Council was encroaching on more democratic bodies, like the 192-member United Nations General Assembly.

Other developing nations, like Peru and Panama and small island states, among the most threatened by climate change, agreed with Britain. So did Secretary General Ban Ki-moon. “Projected changes in the earth’s climate are thus not only an environmental concern,” Mr. Ban said. “And, as the Council points up today, issues of energy and climate change can have implications for peace and security.”

The United States, the world’s largest emitter of greenhouse gases that spur climate change, opposes mandatory caps on emissions but has instead pushed alternative fuels and energy efficiency.

The acting American ambassador, Alejandro D. Wolff, said the issue must be dealt with in a way that does not effect economic growth and development.

Most industrial nations, including the European Union, agreed with Britain. As did Papua New Guinea, head of the Pacific small island states, which fear they may disappear under rising oceans levels as the earth warms up.

“The dangers that the small island states and their populations face are no less serious than those nations threatened by guns and bombs,” Ambassador Robert Guba Aisi of Papua New Guinea told the Council.

Italy’s deputy foreign minister, Vittorio Craxi, said members should support Mr. Ban’s effort to create a new United Nations Environmental Organization to coordinate action on climate change.

“It is clear that climate change can pose threats to national security,” said Ambassador Kenzo Oshima of Japan. “In the foreseeable future climate change may well create conditions or induce circumstances that could precipitate or aggravate international conflicts.”